Today, a trend for commercial electronic devices is to integrate more and more functionality therein to attract consumers. To operate these electronic devices, more and more buttons are thus required.
FIG. 1 illustrates the typical button structure including a key 100, an elastomer 102 and a trigger 104. When a user pushes the key 100, the elastomer 102 is deformed to force the trigger 104 down to touch a film switch formed on the printed circuit board 106 to trigger a special circuit for realizing a special functionality. Typically, the elastomer 102 is a spring. However, an additional elastomer 102 is required in this typical button structure. Therefore, such a structure does not offer optimum integration.
To overcome the foregoing drawback, a cantilever is typically used to replace the elastomer. FIG. 2 illustrates this improved button structure. A cantilever 202 is connected to the housing 200. A key 204 is connected to the cantilever 202. When a user pushes the key 204, the cantilever 202 is bent to force the key 204 down to touch a film switch formed under the key 204. Then, a recovery force provided by the cantilever 204 causes the key 204 to return to its original position. Although the improved button structure offers better integration, the elasticity is related to the length of the cantilever 202. When a larger elasticity is required, the cantilever 204 has to be lengthened. Such a structure renders the cantilever 204 to be easily broken. Moreover, a hole formed in the housing 200 is necessary for forming the cantilever 204. A bigger hole is required for forming a longer cantilever 204 to provide a larger elasticity, which often uglifies the overall appearance.
Therefore, an integrated button structure is required.